(1) Field of the Invention
The present invention relates to a method of managing electric power consumption, and more particular to a method that is applied to working power supply of a portable computer.
(2) Description of Prior Art
To seek for better working efficacy of portable computer of the present day, the operating speed and capability of mobile CPU, which is particularly used for portable computer, has been enhanced, therefore, power consumption of mobile CPU is relatively increased, and further causes higher heat to computer. Hence, both Intel and Microsoft have provided excellent electric power management for mobile CPU of portable computer, such as Advanced Configuration and Power Interface (ACPI) and Speed step. ACPI has defined five states from C0˜C4, the higher states have better efficacy of the electric power management. However, mobile CPU of portable computer still has some drawbacks, e.g., the newly promoted mobile CPU speed of portable computer on the market always falls behind DESK TOP CPU of Desktop PC at three to six months, but its selling price is higher than Desktop PC; the production cost, therefore, can not be reduced.
Seeing that mobile CPU of portable computer causes higher cost, the production lines of many portable computer manufacturers have focused on producing DESK TOP CPU of Desktop PC for replacing mobile CPU of portable computer. Consequently, two kinds of CPUs, DESK TOP CPU and mobile CPU, for portable computers are generated; nevertheless, the reserved mobile CPU for the use of portable computer is able to support Speed step and states C0 to C4 to achieve effective electric power management; whereas DESK TOP CPU of Desktop PC can not support Speed step, in addition, the ACPI thereof can support state C2 only.
Besides, DESK TOP CPU of Desktop PC at P4 2.4 GHz/533 has to consume 10 W of electric power only during the period of idle mode; furthermore, CPU at 2.6 GHz/2.8 GHz at least consumes 15 W of electric power during the period of idle mode. Therefore, it is hard to imagine how many batteries are required for operating a portable computer over two hours at the battery mode.
Seeing that the requirement of information processing devices with the mobility quality in modern society is increasing, the goal of unceasingly producing lighter and smaller portable computer will definitely result in the gradual decrease of portable computer in the future to become a production trend. Nevertheless, considering that a mobile worker operates his/her portable computer in an environment where is not necessary to equip with electric power, hence, each portable computer has a built-in battery for supplying required electric power for peripheral computer apparatus, such as a monitor, a disc, a keyboard and a mouse, etc. However, the built-in battery can not supply with required electric power for a portable computer in a long time.
Inasmuch as there is nothing to do with electric power replenishment with the poor progress of battery capability, how to manage electric power consumption of portable computer, which applies DESK TOP CPU of Desktop PC, in addition, effectively prolong the time of battery usage have become technique subjects to be solved.